Acrylamidoalkyl trialkylammonium chorides, such as methacrylamidopropyltrimethylammonium chloride, are important monomers for producing water-soluble cationic polymers. These are mainly used as flocculants and retention auxiliaries in the production of paper. Generally, the polymerizates produced from acrylamido- and methacrylamidoalkyltrimethylammonium chlorides are excellent flocculants and dewatering agents for waste-water purification.
Heretofore, the quaternization has been performed with methyl chloride in an aqueous solution. The ammonium chlorides thus obtained are not crystalline but are dissolved in water. The principle disadvantages of this procedure are that the conversion is usually performed at a temperature ranging from 60.degree. C. to one that is substantially higher. Additionally, the presence of water results in undesired hydrolysis products. Another disadvantage is that the impurities in the starting monomer must be eliminated by treatment steps, such as with active carbon, in a subsequent stage of the process.